1. Field of the Invention.
This invention pertains to article coating, and more particularly to methods and apparatus for coating the surfaces of golf club heads.
2. Description of the Prior Art
It is well known to clad ferrous and non-ferrous substrates with thin coatings of dissimilar materials. Coating is often undertaken to change the surface qualities of the substrate, such as to improve hardness, wear resistance, corrosion resistance, and appearance. For example, it is known to treat the surfaces of cutting tools by such processes as black oxidizing, nitriding, electrolytic plating, chemical vapor deposition, and physical vapor deposition.
Exemplary metallic coatings and sub-coatings for various substrates are described in U.S. Pat. No. 4,556,607, the specification of which is incorporated by reference herein. A few applications of the coatings and sub-coatings are also given in the foregoing patent. However, a description of materials, apparatus, and processes required to successfully coat a golf club head is lacking.
Coating golf club heads presents certain difficulties not encountered in most other coating applications. A particular difficulty is that the bore in the club head hozzle tends to distort when subjected to the heat of a coating furnace. As a consequence, it is usually necessary to remachine the hozzle bore before the head can be assembled to the club handle. To efficiently manufacture a golf club head with a coating of the U.S. Pat. No. 4,556,607 patent or any other coating, therefore, it is first necessary to discover a way to prevent hozzle bore distortion during the coating process.